From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A14B2106F2EB for ; Thu, 26 Mar 2026 08:02:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E5D836B0005; Thu, 26 Mar 2026 04:02:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E0F086B0088; Thu, 26 Mar 2026 04:02:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D24546B0089; Thu, 26 Mar 2026 04:02:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id BF2766B0005 for ; Thu, 26 Mar 2026 04:02:23 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 7458FE112E for ; Thu, 26 Mar 2026 08:02:23 +0000 (UTC) X-FDA: 84587471766.10.007C2C1 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf08.hostedemail.com (Postfix) with ESMTP id EA4F7160006 for ; Thu, 26 Mar 2026 08:02:21 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=AT5Q7FdA; spf=pass (imf08.hostedemail.com: domain of ljs@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=ljs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1774512141; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=kb8dhfpjttQqeUBou/rHdhjeiNSx/oLXCj1by7qGXKc=; b=YIQhuqU81n3bNzkJOhjximKTdcJVY1FJwtXMsvIFubSK/8KEU9J97sqL1X1g7i8exd/iSe NlLY3qqIXutr6DTw8WqN2ssy3xO+7+PJYNK8hXrfXfi25g2v1fQMBAZgwarObccjjNC2In KXNQUsAhKP6RzkT7Y3fmqPZFvkKL7KA= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=AT5Q7FdA; spf=pass (imf08.hostedemail.com: domain of ljs@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=ljs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1774512141; a=rsa-sha256; cv=none; b=Qz4bQxAIroXwqCSgy3463oyfPA0esumDRgUiAfhGNTIr/Y3WedqSzbDGHeD7WSM3gT3ZIU RhDkXZ2Me2Nd7hq+niTt1njh1Vn+1rozP2Y+Ygak93BMqRZXIiFbk92ivZuY4Uj1ewpbFP Bbfd9vYg1up2CSGg+nt+5N/qt+sxKiM= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 4388C60053; Thu, 26 Mar 2026 08:02:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8DF66C116C6; Thu, 26 Mar 2026 08:02:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774512141; bh=A48kUkO1TtrycoKeHx6/YYvUwwXAqNBRegZ4mzWsWV4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AT5Q7FdAlt3PjmHZzDskG9ydXKEAAtzJIYmfbCnqz4kza5CM8AFrdE85fKpjjpwaL Fz9NS3JMR46gZG5WOmxUP+m5ol0ITjKrkBLpYaITOCWuvUtvlKoQEt2i1TmNgJ/5kT /vi2HHCpuLyAfLcrIv1VF8ZsQRsxuZfS9Hh5aAW7+I6XJHo62HxOFe2X3k7t2y+kbd anSt8hYP/MrBl7AOcj1nDnufgSjSZIu6bGXfQ9Q/f0ItuTNirDMGrO63KUZUNRjO2Z 2LP7Gpg2SrePNK7jtESKiWS6TcJFkG1iMO13I1S/ZMPZJ4ikkWCDcS1pdefCZXu+R3 SviBOW7FWSV/w== Date: Thu, 26 Mar 2026 08:02:12 +0000 From: "Lorenzo Stoakes (Oracle)" To: Michal Hocko Cc: Andrew Morton , Shakeel Butt , lsf-pc@lists.linux-foundation.org, Johannes Weiner , David Hildenbrand , Qi Zheng , Chen Ridong , Emil Tsalapatis , Alexei Starovoitov , Axel Rasmussen , Yuanchu Xie , Wei Xu , Kairui Song , Matthew Wilcox , Nhat Pham , Gregory Price , Barry Song <21cnbao@gmail.com>, David Stevens , Vernon Yang , David Rientjes , Kalesh Singh , wangzicheng , "T . J . Mercier" , Baolin Wang , Suren Baghdasaryan , Meta kernel team , bpf@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [LSF/MM/BPF TOPIC] Towards Unified and Extensible Memory Reclaim (reclaim_ext) Message-ID: References: <20260325210637.3704220-1-shakeel.butt@linux.dev> <20260325190547.abb7309fb63473b57b7a90a0@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: EA4F7160006 X-Stat-Signature: m1qdcbgqnqfwzfpc8e6jc5y9uwrawrfz X-Rspam-User: X-HE-Tag: 1774512141-428197 X-HE-Meta: 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Mar 26, 2026 at 08:03:34AM +0100, Michal Hocko wrote: > On Wed 25-03-26 19:05:47, Andrew Morton wrote: > > On Wed, 25 Mar 2026 14:06:37 -0700 Shakeel Butt wrote: > > > > > We should unify both algorithms into a single code path. > > > > I'm here to ask the questions which others fear will sound dumb. > > Not dumb at all and recently discussed here https://lore.kernel.org/all/CAMgjq7AkYOtUL2HuZjBu5dJw=RTL7W2L1+zVv=SCOyHKYwc3AA@mail.gmail.com/T/#u > > > Is it indeed the plan to maintain both implementations? I thought the > > long-term ambition was to knock MGLRU into shape and to drop the legacy LRU? > > Yes, but MGLRU is not there yet and with development pace last year or > so we are not much closer than at the time MGLRU has been merged > unfortunatelly. I'm quite concerned about maintainership, as it seems the MGLRU maintainers have not been all that active, and the MGLRU to me at least is currently a black box. I'm not the only one who's raised this (see [0]). That'd very much have to be resolved and the community reassured that MGLRU is _actively_ maintained before we could even contemplate it replacing the 'classic' reclaim approach IMO. I hope that Kairu, Barry, Zicheng and others who are interested int it resolve this, however! Thanks, Lorenzo [0]:https://lore.kernel.org/linux-mm/aaBsrrmV25FTIkVX@casper.infradead.org/ > -- > Michal Hocko > SUSE Labs